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Group consensus of multi-agent systems with additive noises

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Science China(Information Sciences) 2022年第10期65卷 242-255页

作者： Chuanjian li Xiaofeng zong School of Automation China University of Geosciences Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems Engineering Research Center of Intelligent Technology for Geo-Exploration Ministry of Education

This paper is concerned with group consensus of multi-agent systems(MASs) that consist of two groups in additive noise environments. First, a control protocol is proposed based on the state information of each agent’s neighbors corrupted by additive noises. Second, some sufficient conditions and necessary conditions are obtained for the following two types of group consensus behaviors.(1) Pure group consensus:agents in both groups have the same behavior(weak consensus or strong consensus);(2) hybrid group consensus: agents in different groups achieve different consensus behaviors. It is revealed that the influence between the two groups should be attenuated such that the MASs can achieve group consensus in additive noise environments, i.e., the affected group must fight against the influence that comes from another group.Finally, some simulation examples are given to illustrate the feasibility of the theoretical results.

关键词： group consensus multi-agent systems additive noises pure group consensus hybrid group consensus

A numerical study of hydrodynamic influence on collision of brash ice with a structural plate

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Journal of Hydrodynamics 2022年第1期34卷 43-51页

作者： li Zhou Zhi zong Jia-nan li School of Naval Architecture Dalian University of TechnologyDalian116024China Tianjin Branch HuaDian Heavy Industries Co.Ltd Tianjin300010China

The ice-structure collision is a transient process, which is further complicated by the presence of the water. It remains unclear how important the hydrodynamic influences are during the collision. This problem is partially investigated in this paper using numerical methods. To simplify the problem as much as possible without loss of generality, a short ice cylinder of circular section is assumed to collide with a vertical large structure plate under a variety of collision scenarios. Among them the most important cases are: (1) the rigid ice cylinder collision with the rigid or elastic structural plate at different collision velocities, (2) the elastic ice cylinder collision with the rigid or elastic structural plate at different collision velocities and (3) the elastoplastic ice cylinder collision with the rigid or elastic structural plate at different collision velocities. The numerical results show that: (1) the hydrodynamic influences are negligible in the first case, (2) the hydrodynamic influences in the second and third cases are not negligible, and become very significant in the third case. The influences are numerically estimated to be in the range of 20%–60% in terms of the momentum change. If the ice response is approximately decomposed into the rigid-body motions and the deformation modes at the instant of the collision with the structure, the previous conclusions show that the hydrodynamic influences on the rigid-body motions of the ice are negligible, but those on the elastic and elastoplastic modes of the ice are significant. Comparison with the case of a submerged ice cylinder (although not a practical case) reveals that the hydrodynamic influences are small in the first case due to the fact that the energy loss is used to produce the water splash and the cavity behind the ice cylinder. Through this study we come into the conclusion that the hydrodynamic influences are not important for the rigid-body motions, but important for the elastic or elastoplastic modes.

关键词： Ice-structure collision hydrodynamic influence numerical rigid mode elastic mode

Height and body mass index trajectories from 1975 to 2015 and prevalence of stunting,underweight and obesity in 2016 among children in Chinese cities:findings from five rounds of a national survey

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World Journal of Pediatrics 2024年第4期20卷 404-412页

作者： Xin‑Nan zong Hui li Ya‑Qin Zhang Department of Growth and Development Capital Institute of PediatricsBeijing 100020China

Background A more comprehensive assessment of growth and nutrition in children is required in China due to rapid socioeconomic processes.We aimed to investigate height and body mass index(BMI)trajectories from 1975 to 2015 and the prevalence of stunting and obesity in 2016 among children in Chinese cities.Methods A total of 904,263 children from birth to 6.9 years were collected from a series of nationally representative surveys in China.Height and BMI trajectories and prevalence of stunting,underweight,overweight and obesity were assessed.Results The average height level of Chinese urban children under 7 years presented a positive secular trend from 1975 to 2015;however,a slowing tendency occurred in 2005‒2015.An apparent increase was observed at the 5th,50th and 95th percentiles of BMI in urban children aged 3 years and older,with a more prominent increase at the 95th percentile.The total prevalence of stunting and underweight under 7 years was 1.4%and 2.0%,respectively.The total prevalence of overweight and obesity under 7 years was 12.6%and 4.3%,respectively,with 12.7%and 4.9%for boys,12.6%and 3.6%for girls,12.1%and 4.0%in urban areas and 13.1%and 4.5%in suburban rural areas.Conclusions The average height level of Chinese urban children has reached World Health Organization child growth standards since 2005 and presented a slowing tendency in secular trend in 2005‒2015.More attention and efforts and public health interventions should be urgently made to combat overweight and obesity among preschool children.

关键词： Body mass index Children Height Obesity Stunting

Deep learning-based on-line image analysis for continuous industrial crystallization processes

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Particuology 2023年第3期74卷 173-183页

作者： Shiliang zong Guangzheng Zhou Meng li Xuezhong Wang Beijing City Key Laboratory of Enze Biomass and Fine Chemicals College of New Materials and Chemical EngineeringBeijing Institute of Petrochemical TechnologyBeijing102617China

In situ microscopic imaging is a useful tool in monitoring crystallization processes,including crystal nucleation,growth,aggregation and breakage,as well as possible polymorphic transition.To convert the qualitative information to be quantitative for the purpose of process optimization and control,accurate analysis of crystal images is essential.However,the accuracy of image segmentation with traditional methods is largely affected by many factors,including solid concentration and image quality.In this study,the deep learning technique using mask region-based convolutional neural network(Mask R-CNN)is investigated for the analysis of on-line images from an industrial crystallizer of 10 m^(3) operated in continuous mode with high solid concentration and overlapped particles.With detailed label points for each crystal and transfer learning technique,two models trained with 70,908 and 7,709 crystals respectively are compared for the effect of training data amount.The former model effectively segments the aggregated and overlapped crystals even at high solid concentrations.Moreover,it performs much better than the latter one and traditional multi-scale method both in terms of precision and recall,revealing the importance of large number of crystals in deep learning.Some geometrical characteristics of segmented crystals are also analyzed,involving equivalent diameter,circularity,and aspect ratio.

关键词： Continuous crystallization Crystal shape Image analysis Deep learning Instance segmentation Process analytical technology

Apoptotic mechanism of premature ovarian failure and rescue effect of Traditional Chinese Medicine: a review

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Journal of Traditional Chinese Medicine 2021年第3期41卷 491-498页

作者： CAI liang zong Daokuan TONG Guoqing li li Department of Reproductive Center Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203China

Social and environmental factors render premature ovarian failure(POF) as a major cause of decline or loss of female fertility. The natural pregnancy rate of patients with POF is only 5%-10%. Follicular atresia is the main factor in the pathogenesis of POF.Due to the unique ovarian physiological environment and follicular developmental processes, the apoptosis of ovarian granulosa cells and oocytes together cause follicular atresia, which involves the apoptosis-related internal and external pathways.Furthermore, during POF, apoptosis and oxidative stress forms a "vicious circle", which involves a variety of changes between the molecules. The existing pharmaceutical preparations such as gonadal hormones are the basic methods for the treatment of POF, and the curative effect was affirmative;however, it was ineffective after withdrawn, while the long-term application led to adverse reactions. Traditional Chinese Medicine(TCM) has a history of treating gynecological diseases and infertility and has gained increasing attention. Studies have shown that compounds isolated from herbal medicine exerted a positive effect on follicular atresia caused by cell apoptosis that also improved the POF. The present study reviewed the mechanisms underlying the apoptosis in POF and elaborated the internal mechanism of TCM in the treatment of the condition.

关键词： primary ovarian insufficiency apoptosis oxidative stress drugs Chinese herbal review

维普期刊数据库

Numerical simulation of Marangoni effect induced by species transfer across iron droplet–molten slag interface

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Journal of Iron and Steel Research(International) 2023年第6期30卷 1109-1116页

作者： Ming-ming li Zhen-qiang Wu lin li zong-shu Zou Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819LiaoningChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina School of Metallurgical Engineering Liaoning Institute of Science and TechnologyBenxi 117004LiaoningChina

A mathematical model accounting for unsteady mass transfer across interface of a stationary iron droplet immersed into molten slag was established through the volume of fluid coupled with level set method.The Marangoni effect induced by mass transfer was reproduced successfully,and the hydrodynamic instability phenomena at the interface,such as the Marangoni convection flow,the evolution of the interfacial tension during the mass transfer,and the influence of Marangoni effect on the mass transfer rate,were revealed.The results show that the Marangoni convection flow develops quickly and behaves as an ordered structure in the forms of four pairs of the convection cell at the edge of the droplet once the oxygen transfer across the interface starts.The average convection flow velocity along the interface is high,even more than 0.025 m/s,depending on the droplet diameter,which facilitates the mass transfer.The Marangoni convection flow of the large droplet develops more easily than that of the small droplet,and the larger the droplet diameter is,the higher the convection flow velocity and the mass transfer rate are.Moreover,it is shown that the droplet diameter influences the impacting region of the Marangoni convection flow and its duration period.

关键词： Interfacial mass transfer Interfacial tension Marangoni effect Droplet Numerical simulation

Facies-constrained prestack seismic probabilistic inversion driven by rock physics

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Science China Earth Sciences 2020年第6期63卷 822-840页

作者： Kun li Xingyao YIN Zhaoyun zong School of Geosciences China University of Petroleum(East China)Qingdao 266580China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China

Seismic Rock physics plays a bridge role between the rock moduli and physical properties of the hydrocarbon reservoirs.Prestack seismic inversion is an important method for the quantitative characterization of elasticity,physical properties,lithology and fluid properties of subsurface reservoirs.In this paper,a high order approximation of rock physics model for clastic rocks is established and one seismic AVO reflection equation characterized by the high order approximation(Jacobian and Hessian matrix)of rock moduli is derived.Besides,the contribution of porosity,shale content and fluid saturation to AVO reflectivity is analyzed.The feasibility of the proposed AVO equation is discussed in the direct estimation of rock physical properties.On the basis of this,one probabilistic AVO inversion based on differential evolution-Markov chain Monte Carlo stochastic model is proposed on the premise that the model parameters obey Gaussian mixture probability prior model.The stochastic model has both the global optimization characteristics of the differential evolution algorithm and the uncertainty analysis ability of Markov chain Monte Carlo model.Through the cross parallel of multiple Markov chains,multiple stochastic solutions of the model parameters can be obtained simultaneously,and the posterior probability density distribution of the model parameters can be simulated effectively.The posterior mean is treated as the optimal solution of the model to be inverted.Besides,the variance and confidence interval are utilized to evaluate the uncertainties of the estimated results,so as to realize the simultaneous estimation of reservoir elasticity,physical properties,discrete lithofacies and dry rock skeleton.The validity of the proposed approach is verified by theoretical tests and one real application case in eastern China.

关键词： Prestack seismic inversion Seismic rock physics Physical properties estimation Bayesian inference Probabilistic mixture model Markov chain Monte Carlo

维普期刊数据库

Cradle for the newborn Monochamus saltuarius:Microbial associates to ward off entomopathogens and disarm plant defense

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Insect Science 2023年第4期30卷 1165-1182页

作者： Si-Xun Ge Jia-Xing li Zhuo-Heng Jiang Shi-Xiang zong li-li Ren Bejing Key Laboratory for Forest Pest Control Bejing Forestry UniversityBeijingChina School of Science Westlake UniversityHangzhouChina Sino-French Joint Laboratory for Invasive Forest Pests in Eurasia Bejing Forestry University-French National Research Institute for AgricultureFood and Environment(INRAE)BejingChina

The Japanese pine sawyer,Monochamus saltuarius,as a beetle vector of Bur-saphelenchus xylophilus(pine wood nematode),is an economically important forest pest in Eurasia.To feed on the phloem and xylem of conifers,M.saltuarius needs to overcome various stress factors,including coping with entomopathogenic bacteria and also various plant secondary compounds(PSCs).As an important adaptation strategy to colonize host trees,M.saltuarius deposit eggs in oviposition pits to shield their progeny.These pits har-bor bacterial communities that are involved in the host adaptation of M.saltuarius to the conifers.However,the composition,origin,and functions of these oviposition pit bacteria are rarely understood.In this study,we investigated the bacterial community associated with M.saltuarius oviposition pits and their ability to degrade PSCs.Results showed that the bacterial community structure of M.saltuarius oviposition pits significantly differed from that of uninfected phloem.Also,the oviposition pit bacteria were predicted to be enriched in PSC degradation pathways.The microbial community also harbored a lethal strain of Serratia,which was significantly inhibited.Meanwhile,metatranscriptome anal-ysis indicated that genes involved in PSCs degradation were expressed complementarily among the microbial communities of oviposition pits and secretions.In vitro degrada-tion showed that bacteria cultured from oviposition pits degraded more monoterpenes and flavonoids than bacteria cultured from uninfected phloem isolates.Disinfection of ovipo-sition pits increased the mortality of newly hatched larvae and resulted in a significant decrease in body weight in the early stages.Overall,our results reveal that M.saltuarius construct oviposition pits that harbor a diverse microbial community,with stronger PSCs degradation abilities and a low abundance of entomopathogenic bacteria,resulting in the increased fitness of newly hatched larvae.

关键词： community structure entomopathogenic bacteria host plant adaptation plant secondary metabolites symbiotic bacteria

Comparison of updated birth weight,length and head circumference charts by gestational age in China with the INTERGROWTH-21 st NCSS charts:a population-based study

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World Journal of Pediatrics 2023年第1期19卷 96-105页

作者： Ya-Qin Zhang Hui li Xin-Nan zong Hua-Hong Wu Department of Growth and Development Capital Institute of PediatricsNo.2Ya Bao RoadChaoyang DistrictBeijingChina

Background INTERGROWTH-21 st Newborn Cross-Sectional Study(NCSS)charts were established and recommended for global application.However,whether one international reference is appropriate for all populations is still unclear.We aim to compare the updated Chinese birth size charts by gestational age with INTERGROWTH-21st NCSS charts.Methods A cross-sectional survey was carried out,and the birth weight,length and head circumference of 24,375 infants born after uncomplicated pregnancies at gestational age ranging from 24+0 to 42+6 weeks were measured in 13 cities in China from 2015 to 2018.Growth charts were constructed.The measurements of all these infants were evaluated by the methods of calculating their Z scores using the INTERGROWTH-21 st standards.The prevalence of small for gestational age(SGA)and large for gestational age(LGA)based on birth weight was analyzed using Chinese charts and INTERGROWTH-21st charts.Results The mean Z scores were 0.10 for birth weight,0.35 for length and-0.02 for head circumference.Compared to the INTERGROWTH-21st charts,the Chinese birth weight percentile curves were higher except for the 90th percentile at 29-37 weeks gestational age,and the length percentile curves were higher after 33 weeks gestational age,while the 10th percentile of the head circumference was lower and the other percentiles were similar.The prevalence of SGA was 10.1%[95%confidence interval(CI)=9.7%-10.5%]using the Chinese birth weight chart and 6.5%(95%CI=6.2%-6.8%)using the INTERGROWTH-21 st birth weight chart.The prevalence of LGA was 9.9%(95%CI=9.5%-10.2%)and 8.2%(95%CI=7.9%-8.6%)using the Chinese and INTERGROWTH-21st birth weight charts,respectively.Conclusions Chinese birth size charts based on infants born after uncomplicated pregnancies were different from the INTER-GROWTH-21st charts.Differences in the classification of newborns by the two charts should receive attention,and whether the application of INTERGROWTH-21st in Chinese newborns will lead to misclassification needs to be validated in future cli

关键词： Birth length Birth weight Growth charts Head circumference Newborns